 /*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

        package com.android.ninepatch;

        import javax.imageio.ImageIO;
        import java.awt.image.BufferedImage;
        import java.awt.image.Raster;
        import java.awt.GraphicsConfiguration;
        import java.awt.GraphicsEnvironment;
        import java.awt.Graphics;
        import java.awt.Transparency;
        import java.net.URL;
        import java.io.IOException;
        import java.io.InputStream;

        public class GraphicsUtilities {
            public static BufferedImage loadCompatibleImage(URL resource)
                    throws IOException {
                BufferedImage image = ImageIO.read(resource);
                return toCompatibleImage(image);
            }

            public static BufferedImage loadCompatibleImage(InputStream stream)
                    throws IOException {
                BufferedImage image = ImageIO.read(stream);
                return toCompatibleImage(image);
            }

            public static BufferedImage createCompatibleImage(int width,
                    int height) {
                return getGraphicsConfiguration().createCompatibleImage(width,
                        height);
            }

            public static BufferedImage toCompatibleImage(BufferedImage image) {
                if (isHeadless()) {
                    return image;
                }

                if (image.getColorModel().equals(
                        getGraphicsConfiguration().getColorModel())) {
                    return image;
                }

                BufferedImage compatibleImage = getGraphicsConfiguration()
                        .createCompatibleImage(image.getWidth(),
                                image.getHeight(), image.getTransparency());
                Graphics g = compatibleImage.getGraphics();
                g.drawImage(image, 0, 0, null);
                g.dispose();

                return compatibleImage;
            }

            public static BufferedImage createCompatibleImage(
                    BufferedImage image, int width, int height) {
                return getGraphicsConfiguration().createCompatibleImage(width,
                        height, image.getTransparency());
            }

            private static GraphicsConfiguration getGraphicsConfiguration() {
                GraphicsEnvironment environment = GraphicsEnvironment
                        .getLocalGraphicsEnvironment();
                return environment.getDefaultScreenDevice()
                        .getDefaultConfiguration();
            }

            private static boolean isHeadless() {
                return GraphicsEnvironment.isHeadless();
            }

            public static BufferedImage createTranslucentCompatibleImage(
                    int width, int height) {
                return getGraphicsConfiguration().createCompatibleImage(width,
                        height, Transparency.TRANSLUCENT);
            }

            public static int[] getPixels(BufferedImage img, int x, int y,
                    int w, int h, int[] pixels) {
                if (w == 0 || h == 0) {
                    return new int[0];
                }

                if (pixels == null) {
                    pixels = new int[w * h];
                } else if (pixels.length < w * h) {
                    throw new IllegalArgumentException(
                            "Pixels array must have a length >= w * h");
                }

                int imageType = img.getType();
                if (imageType == BufferedImage.TYPE_INT_ARGB
                        || imageType == BufferedImage.TYPE_INT_RGB) {
                    Raster raster = img.getRaster();
                    return (int[]) raster.getDataElements(x, y, w, h, pixels);
                }

                // Unmanages the image
                return img.getRGB(x, y, w, h, pixels, 0, w);
            }
        }